This chapter teaches you how to create color boxes in a page of a PDF document.
You can add rectangular boxes in a PDF page using the addRect() method of the PDPageContentStream class.
Following are the steps to create rectangular shapes in a page of a PDF document.
Load an existing PDF document using the static method load() of the PDDocument class. This method accepts a file object as a parameter, since this is a static method you can invoke it using class name as shown below.
File file = new File("path of the document") PDDocument document = PDDocument.load(file);
You need to retrieve the PDPage object of the required page where you want to add rectangles using the getPage() method of the PDDocument class. To this method you need to pass the index of the page where you want to add rectangles.
PDPage page = document.getPage(0);
You can insert various kinds of data elements using the object of the class named PDPageContentStream. You need to pass the document object and the page object to the constructor of this class therefore, instantiate this class by passing these two objects created in the previous steps as shown below.
PDPageContentStream contentStream = new PDPageContentStream(document, page);
You can set the non-stroking color to the rectangle using the setNonStrokingColor() method of the class PDPageContentStream. To this method, you need to pass the required color as a parameter as shown below.
contentStream.setNonStrokingColor(Color.DARK_GRAY);
Draw the rectangle with required dimensions using the addRect() method. To this method, you need to pass the dimensions of the rectangle that is to be added as shown below.
contentStream.addRect(200, 650, 100, 100);
The fill() method of the PDPageContentStream class fills the path between the specified dimensions with the required color as shown below.
contentStream.fill();
Finally close the document using close() method of the PDDocument class as shown below.
document.close();
Suppose we have a PDF document named blankpage.pdf in the path C:\PdfBox_Examples\ and this contains a single blank page as shown below.
This example demonstrates how to create/insert rectangles in a PDF document. Here, we will create a box in a Blank PDF. Save this code as AddRectangles.java.
import java.awt.Color; import java.io.File; import org.apache.pdfbox.pdmodel.PDDocument; import org.apache.pdfbox.pdmodel.PDPage; import org.apache.pdfbox.pdmodel.PDPageContentStream; public class ShowColorBoxes { public static void main(String args[]) throws Exception { //Loading an existing document File file = new File("C:/PdfBox_Examples/BlankPage.pdf"); PDDocument document = PDDocument.load(file); //Retrieving a page of the PDF Document PDPage page = document.getPage(0); //Instantiating the PDPageContentStream class PDPageContentStream contentStream = new PDPageContentStream(document, page); //Setting the non stroking color contentStream.setNonStrokingColor(Color.DARK_GRAY); //Drawing a rectangle contentStream.addRect(200, 650, 100, 100); //Drawing a rectangle contentStream.fill(); System.out.println("rectangle added"); //Closing the ContentStream object contentStream.close(); //Saving the document File file1 = new File("C:/PdfBox_Examples/colorbox.pdf"); document.save(file1); //Closing the document document.close(); } }
Compile and execute the saved Java file from the command prompt using the following commands.
javac AddRectangles.java java AddRectangles
Upon execution, the above program creates a rectangle in a PDF document displaying the following image.
Rectangle created
If you verify the given path and open the saved document — colorbox.pdf, you can observe that a box is inserted in it as shown below.